\documentclass{standalone}
\usepackage{tikz}
\begin{document}
\footnotesize
  \begin{tikzpicture}[>=stealth]
    \draw[thick] (0,0)-- ++(1,0)--++(0,0.8)--++(-1,0);
    \draw[thick] (2.5,-0.3)-- ++(-1,0)--++(0,0.8)--++(1,0);
    \draw[thin] (1,-0.1)--++(0,-0.9)(1.5,-0.4)--++(0,-0.6);
    \draw[thin,<->](1,-0.9)--++(0.5,0)node[midway,above]{$b$};
    \draw[thin] (0,-0.1)--++(0,0.4)--++(150:0.1)--++(30:0.2)--++(150:0.1)--++(0,0.4);
    \draw[thin] (2.5,-0.4)--++(0,0.4)--++(150:0.1)--++(30:0.2)--++(150:0.1)--++(0,0.4);
    \draw[thin] (1.1,0.8)--++(2,0) (2.6,0.5)--++(0.5,0) (2.6,-0.3)--++(0.5,0);
    \draw[thin,<->](3.0,-0.3)--++(0,0.8)node[midway,sloped,above]{$T$};
    \draw[thin,<->](3.0,0.5)--++(0,0.3)node[midway,sloped,above]{$\Delta$};
    \draw[thin] (-0.1,0)--++(-0.5,0) (1.4,-0.3)--++(-2,0);
    \draw[thin,<->](-0.5,-0.3)--++(0,0.3)node[midway,sloped,above]{$\Delta$};
  \end{tikzpicture}
\end{document}